<html class="reftest-wait">
<head>
  <style>
    body   { width:  100px; line-height: 15px; }
    div    { width:  100px; float: left }
    div.a  { height:  30px; background: lightblue;  }
    div.b  { height:  10px; background: lightgreen; }
    div.c  { height:  10px; background: black;      }
  </style>
  <script>
  function tweak() {
    document.getElementById('changeMe').style.height = '100px';
    document.documentElement.className = "";
  }
  </script>
</head>
<body onload="tweak()">
  <div class="a"></div>
  <div class="b" id="changeMe"></div>
  <div class="c"></div>
</body>
</html>
